This invention relates generally to water vessels of the floating-dock type and, more particularly, to floating-dock type vessels which are adapted for seismic or like research.
Vessels of the floating-dock type are intended mainly for transporting floating cargo such, for example, as lighters and timber. Such vessels generally include a pair of spaced side walls, a cargo deck extending between the side walls defining a cargo space, and a door situated at the stern of the vessel. The loading of such vessels is normally performed through the stern door with the ship having been lowered by means of ballast to a suitable depth in the water whereby the cargo can be floated into or out from the cargo space. It is also possible to load ordinary, i.e. dry cargo such, for example, as containers and trailers into some vessels of this type by arranging the cargo in the conventional manner on the cargo deck of the ship. Vessels of the floating-dock type are normally quite large in order to provide adequate capacity for the transportation of lighters. In particularly, the length of such vessels is generally on the order of about 150 m so that such vessels remain quite steady even in rough seas.
On the other hand, vessels intended for seismic or hydrologic research are normally specialized vessels on which research equipment is normally permanently fixed so that such vessels generally cannot be used for any purpose other than research. Conventional research vessels are of a relatively small size, generally having a length on the order of about 50 m and for this reason research work generally cannot be carried out on such vessels in rough seas due to the consequent movement of such vessels.